PYROCRYSTAL S.r.l. projects, manufactures and install on a turnkey basis sand filtering plants, dual media and active carbons


About filtering process
Final aim of filtering is to with-hold suspended substances or to eliminate water turbidity, in particular when it could alter the correct operation of a ionic exchange unit.

Many different treatments could apply and have been studied in function of the different substances to be cleared from the water. 

Generally sand filters containing only quartzite of different granulometry are used as this kind of filter allows a filtration in the order of 50 micron.

For particular applications are used "dual media" filters containing quartzite and anthracite; those allow filtering in the order of 10 micron.


Active carbons filters are used after "dual media" filters to eliminate eventual  residual-Chlorine or chlorinated solvents, detergents or organic toxic polluting. 



Filtering process is held from top to the bottom, when the loss of charge from inlet to outlet reaches values about 0.8-0.9 bar starts a counter-current back wash cleaning. Depending on filters dimensions and filtering bed volume, the back-wash action could be integrated with air blowing by-means a rotary blower.